fix "bundle --stdin" segfault

When passed an empty list, objects_array_remove_duplicates() corrupts it by changing the number of entries from 0 to 1. The problem lies in the condition of its main loop: for (ref = 0; ref < array->nr - 1; ref++) { The loop body manipulates the supplied object array. In the case of an empty array, it should not be doing anything at all. But array->nr is an unsigned quantity, so the code enters the loop, in particular increasing array->nr. Fix this by comparing (ref + 1 < array->nr) instead. This bug can be triggered by git bundle --stdin: $ echo HEAD | git bundle create some.bundle --stdin’ Segmentation fault (core dumped) The list of commits to bundle appears to be empty because of another bug: by the time the revision-walking machinery gets to look at it, standard input has already been consumed by rev-list, so this function gets an empty list of revisions. After this patch, git bundle --stdin still does not work; it just doesn’t segfault any more. Reported-by: Joey Hess <joey@kitenet.net> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jonathan Nieder committed Apr 19, 2010 at 03:03 UTC 97a20eea199f490760cc25b1b7df28361f54e536

1 file changed +2 -2

object.c

+2 -2

@@ -252,10 +252,10 @@ void add_object_array_with_mode(struct object *obj, const char *name, struct obj

252

253 void object_array_remove_duplicates(struct object_array *array)

254 {

255 - int ref, src, dst;

255 + unsigned int ref, src, dst;

256 struct object_array_entry *objects = array->objects;

257

258 - for (ref = 0; ref < array->nr - 1; ref++) {

258 + for (ref = 0; ref + 1 < array->nr; ref++) {

259 for (src = ref + 1, dst = src;

260 src < array->nr;

261 src++) {